21221123121011 has 16 divisors (see below), whose sum is σ = 23406005645568. Its totient is φ = 19079288172000.

The previous prime is 21221123121007. The next prime is 21221123121073. The reversal of 21221123121011 is 11012132112212.

It is a cyclic number.

It is not a de Polignac number, because 21221123121011 - 2² = 21221123121007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221123121811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9834911 + ... + 11796936.

It is an arithmetic number, because the mean of its divisors is an integer number (1462875352848).

Almost surely, 2^{21221123121011} is an apocalyptic number.

21221123121011 is a deficient number, since it is larger than the sum of its proper divisors (2184882524557).

21221123121011 is a wasteful number, since it uses less digits than its factorization.

21221123121011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21632842.

The product of its (nonzero) digits is 96, while the sum is 20.

Adding to 21221123121011 its reverse (11012132112212), we get a palindrome (32233255233223).

The spelling of 21221123121011 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty-three million, one hundred twenty-one thousand, eleven".